Taxonomy of commonly fossilised invertebrates

This includes groups that are significant in paleontological contexts, abundant in the fossil record, or have a high proportion of extinct species.

Special notations are explained below: The paleobiologic systematics that follow are not intended to be comprehensive, rather, they are designed to encompass invertebrates that (a) are popularly collected as fossils and (b) extinct.

Includes fossil genera such as Archaeocyathus, Cambrocyathus, Atikonia, Tumuliolynthus, Kotuyicyathus, Metaldetes, Ajacicyathus and Paranacyathus.

Quintessential true sponges; marine, colonial, pore-bearing animals; organized collar-flagellates; poriferans - today mostly siliceous – half of all documented species of Porifera are fossils and extinct.

[4] Porifera may eventually be broken up into separate phyla: Eumetazoans; true metazoans (typically mobile, multicellular animals).

Eumetazoa contains most of the living and deceased species of recorded life, including most invertebrates (extinct and extant), as well as all vertebrate animals.

The Ordovician cystoid Echinosphaerites (an extinct echinoderm of the Class Rhombifera) from northeastern Estonia ; encrusted by a graptolite (black branches).
Quinqueloculina , a foraminiferan (a type of protist) from Donegal Bay, Ireland.
Pattersonia ulrichi Rauff, 1894; an Ordovician hexactinellid sponge near Cincinnati, Ohio.
Tetractinella trigonella at MUSE - Science Museum in Trento
Aulopora (a tabulate coral) from the Silica Shale (Middle Devonian), northwestern Ohio.
Heterotrypa , a trepostome bryozoan from the Corryville Formation (Upper Ordovician) in Covington, Kentucky.
Rhynchotrema dentatum , a rhynchonellid brachiopod from the Cincinnatian (Upper Ordovician ) of southeastern Indiana.
Peltoceras solidum ammonite from the Matmor Formation (Jurassic, Callovian) in the Matmor Formation, Makhtesh Gadol, Israel.
Vermetid gastropod Petaloconchus intortus attached to a branch of the coral Cladocora ; Pliocene of Cyprus.
Elrathia kingii (trilobite) from the Wheeler Shale (Middle Cambrian), Utah.
Middle Jurassic (Callovian) crinoid pluricolumnals ( Apiocrinites ) from the Matmor Formation in Hamakhtesh Hagadol, southern Israel.
Pendeograptus fruticosus graptolites from the Bendigonian Australian Stage (Lower Ordovician) near Bendigo, Victoria, Australia. Two overlapping, three-stiped rhabdosomes.
Deinosuchus hatcheri at the Natural History Museum of Utah.